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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

2408 results found.

  1. GRB 241030B: AKO Optical Afterglow Detection
  2. GRB 241030B: Nanshan/HMT optical afterglow detection
  3. GRB 241030B: SVOM/ECLAIRs detection of a burst
  4. Konus-Wind detection of GRB 241030A
  5. GRB 241030A: Fermi-LAT detection
  6. GRB 240912A: radio detection with the VLA
  7. GRB 241030A: AKO Optical Afterglow Detection
  8. GRB 241030A: SVOM/GRM observation
  9. GRB 241030A: SVOM/C-GFT optical observations
  10. GRB 241030A: SVOM/VT optical afterglow observations
  11. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  12. GRB 241029A: GROWTH-India Telescope optical follow up
  13. GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
  14. GRB 241029A: Swift-XRT observations
  15. GRB 241029A: Fermi GBM Observation
  16. GRB 241029A: AKO Optical Afterglow Detection
  17. GRB 241029A: GOTO optical afterglow detection
  18. GRB 241029A: Xinglong-2.16m optical afterglow confirmation
  19. GRB 241029A: Mephisto observations
  20. GRB 241029A: TRT optical afterglow candidate detection
  21. GRB 241029A: Swift ToO observations
  22. GRB 241029A: SVOM/GRM observation
  23. GRB 241029A : Detection and localization of a bright long GRB by SVOM/ECLAIRs
  24. GRB 241026A: the 100th GRB detected by GRBAlpha
  25. Konus-Wind detection of GRB 241025A
  26. GRB 241026A: GECAM detection
  27. GRB 241025A: further SAO RAS optical observations
  28. GRB 241026A: SVOM/GRM observation
  29. GRB 241025A: SAO RAS optical observations
  30. GRB 241025A: Mondy optical observations
  31. GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
  32. GRB241025A: 1.3m DFOT optical afterglow detection
  33. ​GRB 241025A: optical photometry from Konkoly
  34. GRB 241025A: GROWTH-India Telescope optical observations
  35. GRB 241025A: COLIBRÍ Detection of the Afterglow
  36. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  37. EP241025a (GRB 241025A): EP observations update
  38. GRB 241025A : SVOM/VT optical afterglow observations
  39. GRB 241001A: JWST spectroscopic identification of a supernova counterpart
  40. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  41. GRB 241025A: SVOM/GRM observation
  42. GRB 241018A: SVOM/C-GFT optical observations
  43. GRB241017A: 1.3m DFOT optical upper limit
  44. GRB 241018A: 1.3m DFOT Optical upper limit
  45. GRB 241018A: EP-FXT afterglow detection
  46. Konus-Wind detection of GRB 241018A
  47. GRB 241018A: SVOM/GRM observation
  48. GRB 241018A/sb24101802: Mephisto optical upper limit
  49. GRB 241017A/sb24101702: Mephisto optical upper limit
  50. GRB 241018A: BOOTES-4/MET optical upper limit
  51. GRB 241018A: Mondy optical upper limit
  52. GRB 241018A: SVOM/VT further analysis and counterpart confirmed
  53. GRB 241018A: GROWTH-India telescope optical upper limit
  54. GRB 241018A: Swift-XRT observations
  55. GRB 241018A: REM optical/NIR upper limits
  56. GRB 241018A: NOT optical observations
  57. GRB 241017A: SVOM/VT follow-up and optical upper limit
  58. GRB 241018A: SVOM/VT follow-up and optical candidate
  59. GRB 241018A: LCO/0.4m optical upper limits
  60. GRB 241018A: Swift ToO observations
  61. GRB 241006A: VIRT Optical Upper Limit
  62. GRB 241018A: X-ray afterglow candidate observed by MXT
  63. GRB 241016B: Fermi GBM Observations
  64. GRB 241018A: Detection of a bright long GRB by SVOM
  65. GRB 241017A: Swift-XRT observations
  66. GRB241017a: Liverpool Telescope observations of XRT uncatalogued sources
  67. GRB 241001A: EP-FXT afterglow detection
  68. GRB 241017A: GROWTH-India Telescope optical upper limit
  69. GRB241017A: TOO Observations by SVOM/MXT
  70. GRB 241016B: Swift/BAT-GUANO localization skymap of a short burst
  71. GRB 241017A: J-band upper limit from WINTER
  72. GRB 241016B: SVOM/GRM observation
  73. GRB 241017A: Swift ToO observations
  74. GRB 241017A : Detection of a weak and soft long duration GRB by SVOM/ECLAIRs
  75. GRB 241013B: Fermi GBM Observation
  76. GRB 241013B: Swift/BAT-GUANO localization skymap of a burst
  77. GRB 241009A: LCO optical upper limits
  78. GRB 241013B: SVOM/GRM observation
  79. GRB 241009A: GRANDMA optical upper limits
  80. GRB 241009A: Swift-XRT afterglow detection
  81. GRB 241009A: Swift ToO observations
  82. GRB 241009A : Detection of a long duration GRB by SVOM/ECLAIRs
  83. EP240930a / GRB 240930B: CrAO ZTSH optical upper limit
  84. GRB 240821A: Host galaxy redshift from VLT/X-shooter
  85. GRB 241006A: SVOM/VT follow-up and optical upper limit
  86. GRB 241001A: Swift-XRT afterglow detection
  87. GRB 240930B: SVOM/C-GFT optical upper limit
  88. GRB 241004A: SVOM/GRM observation
  89. GRB 240930B / EP 240930a: SVOM/GRM observation
  90. GRB 241001A : ECLAIRs spectral analysis and XRF classification
  91. GRB 241002C: SVOM/C-GFT optical upper limit
  92. GRB 241002C: Swift-XRT observations confirm the source to be EI Eri
  93. Konus-Wind detection of GRB 240926A
  94. GRB 241002C: Swift ToO observations
  95. Fermi-GBM Sub-Threshold Detection of GRB 241002D
  96. GRB 241001A : SVOM/VT optical detection
  97. GRB 241002D: SVOM/GRM observation
  98. GRB 241002C: X-ray afterglow candidate observed by SVOM/MXT
  99. GRB 240929A: SAO RAS, Mondy, and CrAO optical observations
  100. GRB 241002C : MITSuME Akeno optical upper limits

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